Birkbeck, Mr., on the finding of new mates by golden eagles.
Birthplace of man.
Births, numerical proportions of the sexes in, in animals and man; male and female, numerical proportion of, in England.
Bischoff, Prof., on the agreement between the brains of man and of the orang; figure of the embryo of the dog; on the convolutions of the brain in the human foetus; on the difference between the skulls of man and the quadrumana; resemblance between the ape’s and man’s.
Bishop, J., on the vocal organs of frogs; on the vocal organs of cervine birds; on the trachea of the Merganser.
Bison, American, co-operation of; mane of the male.
Bitterns, dwarf, coloration of the sexes of.
Biziura lobata, musky odour of the male; large size of male.
Blackbird, sexual differences in the; proportion of the sexes in the; acquisition of a song by; colour of the beak in the sexes of the; pairing with a thrush; colours and nidification of the; young of the; sexual difference in coloration of the.
Black-buck, Indian, sexual difference in the colour of the.